retroactive clairvoyance

Retroactive clairvoyance is
an effect of hindsight bias, whereby one
retrodicts alleged predictions or prophecies. That is, after an event has
occurred, one claims that a psychic had predicted it, albeit in language or
signs too vague or obscure to have been understood prior to the event in
question.

Advocates of the prophetic abilities of Nostradamus are
experts at retroactive clairvoyance, as are those who defend the notion that the Bible
contains a prophetic code. It was only many years
after the rise of Hitler, for example, that the following
verse from Nostradamus was interpreted to be a prediction of Hitler's rise to power:

Beasts mad with hunger will swim across
rivers,
Most of the army will be against the Lower Danube.
The great one shall be dragged in an iron cage
When the child brother will observe nothing.

It took over two millennia for some
statisticians to discover that hidden in the words of the Bible are all
kinds of meaningful messages. Others have applied the same formula to such
books as
War and Peace and The Skeptic's
Dictionary and found similar odd results, indicating that humans
have an uncanny ability to find meaningful patterns where none were
intended.

A common ploy of psychics when a child goes missing is to
provide police with tips based on their "visions." The psychic typically
"sees" something like a dark car, the letter S, the number 5, a torn
shirt, water, a man with a beard, trees, a shallow grave, and other "clues." Later, actual
evidence is retrofitted to match these "clues" (hindsight
bias). The tips that don't fit are
conveniently forgotten (selective thinking) or
facts are distorted, exaggerated, and embellished (retrospective
falsification).

Some police officers actually fall for these tricks, like the sheriff who made
Phil Jordan a deputy for
his alleged help in the Tommy Kennedy
case. In 1975, a six-year old boy got lost in the woods and the police
invited Jordan to help find him. Jordan's version of the story is that he
visualized a map of the area the night before he was called out and that he
led the search team to the boy. The case has been investigated by Joe
Nickell and Ken Feder. Jordan's map was vague and
erroneous. It was of little use in the search. Jordan intentionally went to
an area of the woods that hadn't been searched. He was in a ravine when
others located the lost child, whom they'd heard yelling for help.

The process of finding specific meaning in vague or
ambiguous words, letters, initials, numbers, and so on is called
subjective validation. It is the key
to understanding cold reading, as well as
retroactive clairvoyance and all kinds of divination.